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Old June 26th 05, 11:10 PM
Telamon
 
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In article ,
"Frank Dresser" wrote:

wrote in message
oups.com...
I will have to find the link, but last night I was digging around
in their technical archives and I found a statement to the
effect:"All domestic AM BCB transmitters shall use a 75Us
preemphaisis." I was looking for the maximum analog BW a AM/MW
station could use."


My information might be outdated. Subjectively, though, I think I
hear differences in different stations. I suppose other factors in
the processing might account for any differences.



In the good old days class A stations could go with, I think up to
15KHz BW. I didn't feel like going to my parents and digging
through the 1955~1970 Popular Electroncs that had an article on
this issue.


I'm almost certain that's true. Even 10 kHz of good audio isn't bad,
but I don't hear much of that nowadays.



I am trying to decide if I want to add a ~10KHz ceramic filter to
my outboard detector.


That only allows 5 kHz for normal DSB AM. Will you be limiting the
wideband demodulation to the sync detector?


The best sounding radio I ever had was to connect a good audio
amplifier and speakers up to a crystal radio. There were several local
stations that were very strong signal on this radio and it sounded
fantastic. Never heard anything better since. This was using a real
crystal and cat whisker not a diode in a package. Not much there to
limit the audio response except the Q response curve of the tank
circuit. No filters at all just antenna wire and ground into the tank
circuit followed by the detector and then audio amplifier with speaker.
No need for a fancy design.

--
Telamon
Ventura, California